/*
Copyright (c) [2019??5??1??] [??]
[MBT_studio] is licensed under Mulan PSL v2.
You can use this software according to the terms and conditions of the Mulan PSL v2.
You may obtain a copy of Mulan PSL v2 at:
		 http://license.coscl.org.cn/MulanPSL2
THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
See the Mulan PSL v2 for more details.
*/
#include "stdafx.h"
#include "matrix.h"




#define SWAP_ROWS_DOUBLE(a, b) { double *_tmp = a; (a)=(b); (b)=_tmp; }
#define SWAP_ROWS_FLOAT(a, b) { float *_tmp = a; (a)=(b); (b)=_tmp; }
#define MAT(m,r,c) (m)[(c)*4+(r)]


int Matrix4X4_InvertMatrixf2(const float* m, float* out)
{
	float32 wtmp[4][8];
	float32 m0, m1, m2, m3, s;
	float32 *r0, *r1, *r2, *r3;
	r0 = wtmp[0], r1 = wtmp[1], r2 = wtmp[2], r3 = wtmp[3];
	r0[0] = MAT(m, 0, 0), r0[1] = MAT(m, 0, 1),
			r0[2] = MAT(m, 0, 2), r0[3] = MAT(m, 0, 3),
			r0[4] = 1.0, r0[5] = r0[6] = r0[7] = 0.0,
			r1[0] = MAT(m, 1, 0), r1[1] = MAT(m, 1, 1),
			r1[2] = MAT(m, 1, 2), r1[3] = MAT(m, 1, 3),
			r1[5] = 1.0, r1[4] = r1[6] = r1[7] = 0.0,
			r2[0] = MAT(m, 2, 0), r2[1] = MAT(m, 2, 1),
			r2[2] = MAT(m, 2, 2), r2[3] = MAT(m, 2, 3),
			r2[6] = 1.0, r2[4] = r2[5] = r2[7] = 0.0,
			r3[0] = MAT(m, 3, 0), r3[1] = MAT(m, 3, 1),
			r3[2] = MAT(m, 3, 2), r3[3] = MAT(m, 3, 3),
			r3[7] = 1.0, r3[4] = r3[5] = r3[6] = 0.0;
	/* choose pivot - or die */
	if (fabsf(r3[0]) > fabsf(r2[0]))
		SWAP_ROWS_FLOAT(r3, r2);
	if (fabsf(r2[0]) > fabsf(r1[0]))
		SWAP_ROWS_FLOAT(r2, r1);
	if (fabsf(r1[0]) > fabsf(r0[0]))
		SWAP_ROWS_FLOAT(r1, r0);
	if (0.0 == r0[0])
		return 0;
	/* eliminate first variable     */
	m1 = r1[0] / r0[0];
	m2 = r2[0] / r0[0];
	m3 = r3[0] / r0[0];
	s = r0[1];
	r1[1] -= m1 * s;
	r2[1] -= m2 * s;
	r3[1] -= m3 * s;
	s = r0[2];
	r1[2] -= m1 * s;
	r2[2] -= m2 * s;
	r3[2] -= m3 * s;
	s = r0[3];
	r1[3] -= m1 * s;
	r2[3] -= m2 * s;
	r3[3] -= m3 * s;
	s = r0[4];
	if (s != 0.0) {
		r1[4] -= m1 * s;
		r2[4] -= m2 * s;
		r3[4] -= m3 * s;
	}
	s = r0[5];
	if (s != 0.0) {
		r1[5] -= m1 * s;
		r2[5] -= m2 * s;
		r3[5] -= m3 * s;
	}
	s = r0[6];
	if (s != 0.0) {
		r1[6] -= m1 * s;
		r2[6] -= m2 * s;
		r3[6] -= m3 * s;
	}
	s = r0[7];
	if (s != 0.0) {
		r1[7] -= m1 * s;
		r2[7] -= m2 * s;
		r3[7] -= m3 * s;
	}
	/* choose pivot - or die */
	if (fabsf(r3[1]) > fabsf(r2[1]))
		SWAP_ROWS_FLOAT(r3, r2);
	if (fabsf(r2[1]) > fabsf(r1[1]))
		SWAP_ROWS_FLOAT(r2, r1);
	if (0.0 == r1[1])
		return 0;

	/* eliminate second variable */
	m2 = r2[1] / r1[1];
	m3 = r3[1] / r1[1];
	r2[2] -= m2 * r1[2];
	r3[2] -= m3 * r1[2];
	r2[3] -= m2 * r1[3];
	r3[3] -= m3 * r1[3];
	s = r1[4];
	if (0.0 != s) {
		r2[4] -= m2 * s;
		r3[4] -= m3 * s;
	}
	s = r1[5];
	if (0.0 != s) {
		r2[5] -= m2 * s;
		r3[5] -= m3 * s;
	}
	s = r1[6];
	if (0.0 != s) {
		r2[6] -= m2 * s;
		r3[6] -= m3 * s;
	}
	s = r1[7];
	if (0.0 != s) {
		r2[7] -= m2 * s;
		r3[7] -= m3 * s;
	}

	/* choose pivot - or die */
	if (fabsf(r3[2]) > fabsf(r2[2]))
		SWAP_ROWS_FLOAT(r3, r2);
	if (0.0 == r2[2])
		return 0;

	/* eliminate third variable */
	m3 = r3[2] / r2[2];
	r3[3] -= m3 * r2[3], r3[4] -= m3 * r2[4], r3[5] -= m3 * r2[5], r3[6] -= m3 * r2[6], r3[7] -= m3 * r2[7];
	/* last check */
	if (0.0 == r3[3])
		return 0;
	s = 1.0f / r3[3];             /* now back substitute row 3 */
	r3[4] *= s;
	r3[5] *= s;
	r3[6] *= s;
	r3[7] *= s;
	m2 = r2[3];                  /* now back substitute row 2 */
	s = 1.0f / r2[2];
	r2[4] = s * (r2[4] - r3[4] * m2), r2[5] = s * (r2[5] - r3[5] * m2), r2[6] = s * (r2[6] - r3[6] * m2), r2[7] = s * (r2[7] - r3[7] * m2);
	m1 = r1[3];
	r1[4] -= r3[4] * m1, r1[5] -= r3[5] * m1, r1[6] -= r3[6] * m1, r1[7] -= r3[7] * m1;
	m0 = r0[3];
	r0[4] -= r3[4] * m0, r0[5] -= r3[5] * m0, r0[6] -= r3[6] * m0, r0[7] -= r3[7] * m0;
	m1 = r1[2];                  /* now back substitute row 1 */
	s = 1.0f / r1[1];
	r1[4] = s * (r1[4] - r2[4] * m1), r1[5] = s * (r1[5] - r2[5] * m1), r1[6] = s * (r1[6] - r2[6] * m1), r1[7] = s * (r1[7] - r2[7] * m1);
	m0 = r0[2];
	r0[4] -= r2[4] * m0, r0[5] -= r2[5] * m0, r0[6] -= r2[6] * m0, r0[7] -= r2[7] * m0;
	m0 = r0[1];                  /* now back substitute row 0 */
	s = 1.0f / r0[0];
	r0[4] = s * (r0[4] - r1[4] * m0), r0[5] = s * (r0[5] - r1[5] * m0), r0[6] = s * (r0[6] - r1[6] * m0), r0[7] = s * (r0[7] - r1[7] * m0);

	MAT(out, 0, 0) = r0[4];
	MAT(out, 0, 1) = r0[5], MAT(out, 0, 2) = r0[6];
	MAT(out, 0, 3) = r0[7], MAT(out, 1, 0) = r1[4];
	MAT(out, 1, 1) = r1[5], MAT(out, 1, 2) = r1[6];
	MAT(out, 1, 3) = r1[7], MAT(out, 2, 0) = r2[4];
	MAT(out, 2, 1) = r2[5], MAT(out, 2, 2) = r2[6];
	MAT(out, 2, 3) = r2[7], MAT(out, 3, 0) = r3[4];
	MAT(out, 3, 1) = r3[5], MAT(out, 3, 2) = r3[6];
	MAT(out, 3, 3) = r3[7];
	return 1;
}
